could be a weak laser i've heard people having problems with brawl, then cleaned or tweaked the laser and got it fixed. Brawl mainly has this problem mostly because its a dual layer disc, though this may not be your problem

My lens is fine, since I fixed the problem, I uninstalled cIOS 38 Rev14 I wanted to avoid doing it, from the beginning I knew that was the problem. Not a lot of people know what they're talking about ._.